Nothing surprising in a study we came across from last year, but it is gratifying to see proof.

From ‘What Drives Taxi Drivers?‘ by professors from the department of Economics and Statistics at the University of Innsbruck:

We let the three experimenters always ask for the same service at almost the same time by departing one by one from the same starting point to the same destination. In each triple, two of the experimenters spoke in Greek to the taxi driver, while the third one spoke in English. An experimenter in the role of an English speaking passenger and one experimenter in the role of a Greek speaking passenger stated the destination and asked whether the driver knew the address, adding as an explanation for asking that they were not familiar with the city. The other Greek speaking passenger, however, only stated the destination, but did not say or ask anything else. The purpose of this treatment variation was to manipulate the driver’s perception of the passenger’s familiarity with the city. We hypothesized that passengers revealing that they were unfamiliar with the city would be more prone to being taken on detours.

Varying the passenger’s language (Greek versus English) was meant to manipulate adriver’s perception of the passenger’s familiarity with the details of the local taxi tariff system. Since taxi tariffs are subject to the same regulation all over Greece, speaking Greek was meant to convey to the driver that the passenger is likely to know the general rules for charging, such as when the daytime-tariff applies, or what kind of surcharges are allowed for which services. Since an English speaking passenger is arguably less likely to be perceived as familiar with the details of the Greek taxi tariff system, we hypothesized that taxi drivers tryto exploit their informational advantage in the charging dimension more extensively with English speaking than with Greek speaking passengers.

Finally, we tried to manipulate a driver’s perception of the passenger’s income byvarying the passenger’s clothes and the requested destination. Passengers in the high incomerole always wore a suit and carried a briefcase, while passengers in the low income role weredressed in casual clothes and carried a backpack. If the respective destination was a hotel, itwas either an expensive top-end hotel for high-income passengers or a cheap hostel for lowincome passengers. Assuming that taxi drivers have convex distributional preferences, ourhypothesis was that high-income passengers were more likely to be cheated upon by taxidrivers.

We now turn to a short preview of our main findings. The average length of a ride was 12.9 kilometers (km), of which on average 1 km (8%) was an unnecessary detour. Those passengers who revealed their unfamiliarity with the city were, on average, taken on detours of double length compared to passengers who did not. Overall, in 11% of cases passengers were overcharged through the application of incorrect tariffs. English speaking passengers,who probably conveyed the impression of not being familiar with the details of the tariff system, were overcharged in 19% of the cases, while this happened in only 7% of cases to Greek speaking passengers. Concerning the income dimension, we find that passengers in the role of having high income are taken on longer detours and experience slightly more overcharging.